Past tense of 'demit'; resigned or relinquished an office or position.
Regular past tense formation from 'demit' (from Latin 'demittere'). The -ed ending is standard English past tense marker.
High-ranking officials love using 'demitted office' instead of 'resigned'—it sounds much more dignified and formal, which is probably why we still see it in official government statements today!
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